building an externally housed loop with MCP35X, 2 RX360's to cool a i5-2500k and single 570 SC (second card to come later).

I should be flowing about .90 Gpm ? and looking at just over 5 Deg Delta T? or there abouts. I think from what I am reading I am a bit overkill for the stuff I have now, but should be still in the comfort zone with a second 570.

Most of those rad tests were all done with a single fan in pull, so if you are doing push/pull or shrouding, you can bump those results using the fan modification factors. It's not perfect, but a way to adjust the rad results to better fit variations.